How to remove extra _ and assign one back in the string?

[ybz12003]

Hello:

I would like to remove extra _ from the oldname and assign one _ back to the string.   Please advice how to do it.  Thanks.

data test;

infile datalines dsd;

input Oldname : $150. Newname : $150.;

datalines;

gr__major_get__yes, gr_major_get_yes

gr_img_com___abn_metr_gyr, gr_img_com_abn_metr_gyr

if_excu_con_mer__, if_excu_con_mer

_roi_num_email___view_yes_, roi_num_email_view_yes

;

[ballardw]

Please show the required output. " assign one _ back to the string" is very ambiguous.

[ybz12003 · Accepted solution]

Thanks for asking.  I have figured out by myself. 

[ybz12003]

The output is shown in the newname

[kiranv_]

something like this

newname= prxchange('s/_{2,}/_/',-1, prxchange('s/^_|_$//', -1, trim(oldname)));